Skip to content

Debugging Basics: Finding the GlitchesActivities & Teaching Strategies

Active learning works for debugging basics because young children develop logical reasoning through physical actions. When students move or build according to instructions, they see errors in real time. This immediate feedback helps them connect glitches in sequences to the steps that caused them.

Year 2Technologies4 activities20 min35 min

Learning Objectives

  1. 1Compare the intended outcome of a simple algorithm with its actual result after executing it.
  2. 2Identify the specific instruction causing an error in a given sequence of steps.
  3. 3Design a systematic method for finding and correcting a mistake in a set of instructions.
  4. 4Explain how a single incorrect step can change the final outcome of an algorithm.

Want a complete lesson plan with these objectives? Generate a Mission

Partner Navigation: Buggy Directions

One partner gives a sequence of directions with a deliberate error to guide the other around a taped floor grid to a target. The follower acts it out exactly and reports the mismatch. Partners switch, predict the glitch first, then fix it together.

Prepare & details

Differentiate between an intended action and an actual outcome in a sequence.

Facilitation Tip: During Partner Navigation: Buggy Directions, position yourself to observe pairs and step in if they skip systematic checking, such as reading all instructions before starting.

Setup: Groups at tables with problem materials

Materials: Problem packet, Role cards (facilitator, recorder, timekeeper, reporter), Problem-solving protocol sheet, Solution evaluation rubric

ApplyAnalyzeEvaluateCreateRelationship SkillsDecision-MakingSelf-Management
30 min·Small Groups

Block Sequence Fix: Tower Challenges

Provide cards with step-by-step instructions to build a specific block tower, including one or two errors. In small groups, students predict issues, build anyway, note failures, then revise and rebuild correctly. Record changes on worksheets.

Prepare & details

Predict where an error might occur in a given set of instructions.

Facilitation Tip: During Block Sequence Fix: Tower Challenges, provide a limited set of blocks so students focus on sequence rather than material constraints.

Setup: Groups at tables with problem materials

Materials: Problem packet, Role cards (facilitator, recorder, timekeeper, reporter), Problem-solving protocol sheet, Solution evaluation rubric

ApplyAnalyzeEvaluateCreateRelationship SkillsDecision-MakingSelf-Management
35 min·Whole Class

Class Arrow Hunt: Group Algorithm

Project or display a sequence of arrow cards for the whole class to follow by moving desks or bodies. Pause when the error appears, discuss predictions, vote on fixes, then test the corrected version as a group.

Prepare & details

Design a strategy to systematically find and fix a mistake in a simple algorithm.

Facilitation Tip: During Class Arrow Hunt: Group Algorithm, assign roles like ‘reader’ and ‘checker’ to ensure every student contributes to the debugging process.

Setup: Groups at tables with problem materials

Materials: Problem packet, Role cards (facilitator, recorder, timekeeper, reporter), Problem-solving protocol sheet, Solution evaluation rubric

ApplyAnalyzeEvaluateCreateRelationship SkillsDecision-MakingSelf-Management
20 min·Individual

Pattern Card Debug: Individual Check

Give each student a printed sequence of shapes or colors with errors. They draw or color the expected outcome first, follow steps, identify glitches, and rewrite the algorithm correctly before sharing with a neighbor.

Prepare & details

Differentiate between an intended action and an actual outcome in a sequence.

Facilitation Tip: During Pattern Card Debug: Individual Check, circulate with a checklist to note which students rely on random guesses versus logical steps.

Setup: Groups at tables with problem materials

Materials: Problem packet, Role cards (facilitator, recorder, timekeeper, reporter), Problem-solving protocol sheet, Solution evaluation rubric

ApplyAnalyzeEvaluateCreateRelationship SkillsDecision-MakingSelf-Management

Teaching This Topic

Teach debugging by modeling slow, deliberate checking of each step in a sequence. Avoid rushing to fixes. Research shows that young learners benefit from verbalizing their thought process aloud while following instructions. Use simple, familiar tasks like lining up or building with blocks to ground the concept in their daily experience. Emphasize that debugging is a skill, not a test of perfection.

What to Expect

Successful learning looks like students identifying errors in sequences, explaining why they happened, and correcting them step-by-step. They should work collaboratively to test predictions and revise instructions. By the end, students should confidently check algorithms for accuracy and completeness.

These activities are a starting point. A full mission is the experience.

  • Complete facilitation script with teacher dialogue
  • Printable student materials, ready for class
  • Differentiation strategies for every learner
Generate a Mission

Watch Out for These Misconceptions

Common MisconceptionDuring Partner Navigation: Buggy Directions, students may think errors only happen when directions are given digitally.

What to Teach Instead

Use physical movement sequences with clear visual or auditory cues to show that glitches occur in all instructions. After an error, ask students to act out the corrected version to reinforce that debugging applies to human actions.

Common MisconceptionDuring Block Sequence Fix: Tower Challenges, students may try random changes to fix a tower that doesn’t match the goal.

What to Teach Instead

Pause the activity and model a step-by-step check from the first block to the last. Ask students to point to the step where the tower deviates from the picture. Emphasize that fixes should target the cause, not just the result.

Common MisconceptionDuring Class Arrow Hunt: Group Algorithm, students might assume there is only one error in a long sequence.

What to Teach Instead

Intentionally include two or three errors in the arrow path. During the hunt, ask groups to list every place the path doesn’t match the intended destination. Use peer questioning to challenge assumptions about single errors.

Assessment Ideas

Quick Check

After Partner Navigation: Buggy Directions, provide a new set of directions with one error. Ask students to circle the step that caused the misstep and write one word to describe what went wrong, such as ‘wrong turn’ or ‘missed step’.

Discussion Prompt

During Block Sequence Fix: Tower Challenges, present a tower built incorrectly due to a missing block. Ask students to explain how they would figure out which step was skipped. Listen for responses that mention checking the plan, counting blocks, or comparing to the target tower.

Exit Ticket

After Pattern Card Debug: Individual Check, give each student a card with a buggy pattern instruction (e.g., ‘place red, blue, green blocks’ but the card shows ‘red, green, blue’). Ask them to draw the corrected pattern and write one sentence explaining how they found the error.

Extensions & Scaffolding

  • Challenge: Ask students to create their own buggy algorithm for a peer to debug, using at least three steps with one intentional error.
  • Scaffolding: For students who struggle, provide instructions with highlighted key words or add visuals to each step.
  • Deeper exploration: Introduce a ‘debugging detective’ role where students present a glitch they found in a peer’s work and explain how they located it.

Key Vocabulary

AlgorithmA set of step-by-step instructions to complete a task or solve a problem.
DebuggingThe process of finding and fixing errors, or 'bugs', in a set of instructions or a computer program.
BugAn error or mistake in a set of instructions that causes it to not work as intended.
SequenceThe specific order in which instructions are given or actions are performed.

Ready to teach Debugging Basics: Finding the Glitches?

Generate a full mission with everything you need

Generate a Mission